Fighting in Somalia has been largely along clan lines and economically motivated. But this battle appears to be ideological — over whether Somalia should be governed by Islamic law — fueling what Mogadishu residents described as the worst fighting in more than a decade of lawlessness.

Most of the dead were civilians caught in the crossfire. Fighters began looting some of the homes in between intense fire fights throughout Friday, witnesses said.

More than 280 people have been wounded since Sunday, doctors said.

Clan elders appeared to have abandoned efforts to negotiate a cease-fire.

On Thursday the Islamic force poured dozens of troops into the battle for a strategic road in Somalia's capital. The heavily armed reinforcements arrived in pickup trucks mounted with heavy machine guns.

So far neither side has gained an upper hand in what Mogadishu residents described as the worst fighting in more than a decade of lawlessness.

Militia loyal to the Islamic Court Union have been fighting to capture a strategic road through northern Mogadishu from the alliance. While the alliance has held the road through Sii-Sii, the courts have controlled the neighborhoods on either side.

The alliance accuses the court union of having ties to Al Qaeda, while the Islamic group says the warlords are puppets of the United States.

The courts are popular in Mogadishu because in recent years they have provided the only form of governance in the city, although in the past they have always been divided along clan lines. They are also considered to be fighting for Somalia, not an outside force.

Islamic fundamentalists have portrayed themselves as an alternative capable of bringing order and peace to a country that has had no effective central government since 1991 and have built up their forces as part of a campaign to install an Islamic government in Somalia, something opposed by warlords and a new interim government that has so far been unable to assert much authority because of infighting and insecurity.

The U.N.-backed transitional government has tried to assert control from Baidoa, 240 kilometers (150 miles) west of Mogadishu, because the capital is considered unsafe. Some of the warlords behind the alliance are members of the transitional parliament, although they are fighting the Islamic group on their own.

This latest fighting may only be the beginning. Other clan militias with loose loyalties to both sides have not joined in the fighting yet, but they continue to man defenses in the neighborhoods they control, and tensions are rising.